Details: I think the fic was Post-Thor 2 and Loki ruse as the All-Father has been found out. Odin decides that for Loki to learn his lesson, he will be sent to a realm in which is barren of sentinent life. (Possibly Muspelheim or Svartalfheim) However, Odin decides that Loki should not be alone and use magic to bring Tony to where Loki is at. (The Tony that was taken was possibly from a different point in the time stream than Loki.) Anyway, their both stuck in this realm until the Odin feels like Loki has changed his ways. So Loki and Tony have to find ways to survive the environment they're in. The two of them build a house, a work space for Tony, a garden and raise some livestocks (for some reason chickens comes to mind)? Both of them adjusted to their living conditions when one day a wildfire breaks out near their residence. So they try to salvage what they can head for the river to be safe from the fire. Meanwhile, Thor and Sif have shown up to bring Loki home, when they see the fire. Eventually the fire is put out.
I don't remember what happened after that. Also I think the story was FrostIron (Tony/Loki) but I can't be sure.